Wireless communication systems are being developed with the goal of enabling new services and devices, which will offer new user experiences. One approach to achieve this is to leverage multiple existing radio access technologies (RATs), for example, using a combination of features from wireless wide area networks (e.g., 3G and LTE) and wireless local area networks (e.g., based on WiFi and millimeter wave (mmW)). Dual connectivity (DC) operation enables a wireless device to utilize multiple radio resources provided by multiple distinct schedulers located in more than one access node connected via non-ideal backhaul over the X2 interface.
One challenge with a system that utilizes dual connectivity is how to handle radio link failure failover on the multiple radio resources.